// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "base/files/scoped_file.h"

#include "base/logging.h"
#include "build/build_config.h"

#if defined(OS_POSIX)
#include <errno.h>
#include <unistd.h>

#include "base/debug/alias.h"
#include "base/posix/eintr_wrapper.h"
#endif

namespace base {
namespace internal {

#if defined(OS_POSIX)

    // static
    void ScopedFDCloseTraits::Free(int fd)
    {
        // It's important to crash here.
        // There are security implications to not closing a file descriptor
        // properly. As file descriptors are "capabilities", keeping them open
        // would make the current process keep access to a resource. Much of
        // Chrome relies on being able to "drop" such access.
        // It's especially problematic on Linux with the setuid sandbox, where
        // a single open directory would bypass the entire security model.
        int ret = IGNORE_EINTR(close(fd));

        // TODO(davidben): Remove this once it's been determined whether
        // https://crbug.com/603354 is caused by EBADF or a network filesystem
        // returning some other error.
        int close_errno = errno;
        base::debug::Alias(&close_errno);

        PCHECK(0 == ret);
    }

#endif // OS_POSIX

} // namespace internal
} // namespace base
